Time switches

ABSTRACT

A time switch having at least one electrical switch, on and off actuators for each switch, a driven differential mechanism moving the actuators along a circular path for timed switch operation, manual means for setting the differential mechanism to an instantaneous time of day and having continuously changing time indicating means, and a plurality of manual means each for positioning a different actuator for switch operation at a predetermined time of day and having means to indicate the time of day such actuator will operate the switch.

United State S, Patent [1 1 Durdin t Dec. 11, 1973 TIME SWITCHES [75] Inventor: Peter Robert Durdin, New Malden,

England [73] Assignee: AMF Incorporated, White Plains,

[22] Filed: May 3, 1972 [21] Appl. No.: 249,852

[30] Foreign Application Priority Data May 4,1971 Great Britain"; 13,064/71 [52] US. Cl. 74/112, 74/665 S, 74/674 [51] Int. Cl. Fl6h 27/00 [58] Fieldof Search 74/665 S, 674, 799,

[56] References Cited UNITED STATES PATENTS 2,908,188 10/1959 Maybarduk 74/674 3,138,674 6/1964 'Boyles, 74/3.5 3,079,812

3/1963 Bross 74/3.5

FOREIGN PATENTS OR APPLICATIONS 676,973 8/1957 Great Britain 74/674 375,774 4/1964 Switzerland 74/674 Primary ExaminerManuel A. Antonakas Assistant Examiner--Wesley S. Ratliff, Jr. AttorneyGeorge W. Price et al.

[57] ABSTRACT A time switch having at least one electrical switch, on and off actuators for each switch, a driven differential mechanism moving the actuators along a circular path for timed switch operation, manual means for setting the differential mechanism to an instantaneous time of day and having continuously changing time indicating means, and a plurality of manual means each for positioning a different actuator for switch operation at a predetermined time of day and having means to indicate the time of day such actuator will operate the switch.

12 Claims, 3 Drawing Figures PAFENIEU DEC 1 1 575 SHEET 1 m 3 TIME SWITCHES This invention relates to time switches and more particularly to the setting means of time switches.

It is usual for a time switch to be provided with a dial on which is fitted a tappet or tappets which engage with an associated switching mechanism once during each revolution of the dial.

With time switches intended to repeat daily a given cycle of operations, the time switch must be provided with a calibrated dial to accomodate the 24 hours of a day and which rotates one revolution in 24 hours. With such an arrangement the tappet or tappets are fitted to the dial and must be set at a position or positions on the dial according to the desired cycle of operations. The dial is then set to the actual time of day which is often determined by a pointer to which the actual time of day on the dial is set. With such an arrangement, since the dial is continuously rotating, the presentation of the dial when viewed at any time during a day is con tinuously varying and consequently sometimes causes confusion atthe time of setting the time switch and also sometimes on viewing the time switch.

It is an object of the invention to provide an arrange ment for atime switch which enables the setting means to be more simply presented and once set to remain static at all times during the day, thereby enabling the setting to be more readily understood and therefore more easily set and the set cycle of operation to be viewed at any time with less confusion.

According to the invention, I provide a setting arrangement for a time switch comprising a differential mechanism including a driven gear wheel, a setting gear wheel coaxial with said driven gear wheel, and a pinion in mesh with both the drivenand setting gear wheels, said pinion being rotatable on a shaft which is free to move about the axis of the wheels along a circular path in a plane between the driven and setting gear wheels, said shaft serving to actuate, directly or indirectly, switch mechanism.

If the setting wheel remains stationary when the driven wheel rotates, the pinion will be made to rotate and the pinion shaft will be forced to move along its circular path, i.e., circumferentially at half the speed of the driven wheel.

If the pinion shaft is arranged to engage with a switching mechanism once in every revolution, it will be seen that if the driven wheel rotates at a speed of one revolution every 12 hours, the pinion shaft will rotate along its circular path one revolution every twenty four hours and would thus give a daily operation.

Furthermore if the setting wheel is moved circumferentially from one position to another, the pinion shaft will be made to either advance or retard its position along to circular path with respect to the driven wheel and will be caused to engage with the switching mecha nism at a different time according to the position of the setting wheel.

If therefore one revolution of the setting wheel is made to represent 12 hours and that alternate revolu' tions of the setting wheel are shown to represent AM. and P.M. respectively it will be seen that by setting the setting wheel to any desired time setting the pinion shaft will be offset relative to the driven wheel and caused to engage with the switching mechanism according to the setting of the setting wheel.

Alternatively if the driven wheel is rotated at one rev olution per twenty four hours and the pinion shaft is arranged to actuate the switch mechanism twice in 48 hours, daily operation is again achieved.

The invention will now be described by wayof example with reference to the accompanying drawings in which:

FIG. 1 shows in exploded view an arrangement for operating a set of switch contacts of a time switch, the drive shaft of which is rotated at one revolution per 12 hours,

FIG. 2 shows a device for indicating A.M. or PM. used in conjunction with the time of day dial,

FIG. 3 shows an arrangement comprising four units each operating a set of switch contacts and each being driven by a common shaft which rotates at one revolution per day.

The setting arrangement shown in FIG. 1 comprises a hexagonal shaft driven by a synchronous motor (not shown) the output shaft of which rotates at one revolution per 12 hours. The shaft 10 carries a time-ofday dial ll formed with finger serrations 12 on its periphery and having indicia l3 representing 1 to 12 hours, said dial 1 1 being keyed to said shaft 10. A spacing collar 14 fits freely over the shaft 10.

Next to the collar is provided setting wheel 15 freely rotatable on the shaft 10, which wheel also has finger serrations 16 and indicia 17 representing 1 to 12 hours on its periphery. Formed integrally with the setting wheel 15 is a contrate gear 18 which together with a pinion 19 forms a differential gearing. The pinion 19 is free to rotate on a shaft 21 which moves through a circular path in a plane between the setting wheel 15 and the driven gear 20.

The pinion shaft 21 extends radially from a cam actuator 22 whichis freely rotatable on the shaft 10. The cam actuator is provided, in this example, with one projection 23 for cooperation with a switching cam 24 rotatably mounted on a fixed shaft 46.

A contrate gear 25 driven by the shaft 10 is formed integrally with the gear and forms a double contrate gear 26. The gear is in mesh with a further pinion 27 also engaging a still further contrate gear 28 formed integrally with a further setting wheel 29 carrying finger serrations and indicia.

The pinion 27 is freely mounted on a shaft 30 extending radially from a further cam actuator 31, the shaft being movable in a circular path in a plane between the driven gear wheel 25 and the setting wheel 29. The actuator 31 has one projection 32 which cooperate with the switching cam 33.

In operation the shaft 10, which is rotated at 1 revolution/12 hours, drives the gear wheel 20 which rotates the pinion 19 about its shaft 21. Since the contrate gear 18 on the setting wheel 15 is set in a stationary position the pinion will roll round the contrate gear 18 and accordingly will drive the shaft 21 around its circular path in the same direction as the direction of rotation of the contrate gear 20. The actuator 22 will therefore rotate at half the speed of the driven wheel 20, Le. at 1 rev/24 hrs., and the projection 23 will engage one tooth of the cam 24 on each revolution of the actuator.

The cam 33 is similarly actuated once every 24 hours by the actuator 31 driven via the differential gearing formed by the pinion 27 the settable contrate gear 28 and the driven contrate gear 25.

lf the setting wheel is moved to a new position the contrate gear 18 will cause the pinion 19 to run around the contrate wheel 20, the latter being relatively stationary during the time it takes to set the wheel 15. The pinion will therefore cause the shaft 21 and hence the cam actuator 22 to move to a new position relative to the driven wheel 26 and the dial 11.

Adjustment of the setting wheel 29 similarly causes the actuator 31 to advance or retard in relation to the driven wheel 26 and the dial.

In FIG. 2 an A.M. and P.M. indicator is provided which comprises a cylinder 40 carrying the indicia of A.M. and P.M. The cylinder is mounted on a shaft 41 connected to a cam disc 42 (Geneva motion) having four cut outs 43 engageable in turn by a pin 44 extending from the side of the time-of-day dial 1 1. The dial 1 1 rotates twice in a day and on each revolution the pin rotates the cam disc 42 one quarter so that the letters A.M. and P.M. which are repeated are alternatively viewed. The same arrangement is also fitted to the setting wheels 15, 19 in order to indicate the settings at A.M. or RM.

The arrangement shown in FIG. 3 comprises four differential units, each substantially similar to the arrangement of FIG. 1 except that the main shaft is driven by a clock or synchronous motor at l rev/24 hours.

As before each differential unit comprises a pair of setting gear wheels 50, 51 freely mounted on a drive shaft 52. Between the gear wheels 50, 51 is mounted a double contrate wheel 53 fixed to the shaft 52. Two cam actuators 54,55 are freely mounted on the shaft one on each side of the wheel 53 and actuate respectively two switch earns 56, 57. The actuators each have shafts 48 extending radial of the axis of the wheels carrying pinions 49 meshing with the setting and driven wheels. The actuators each have two diametrically opposed projections 58, 59 and 60, 61. Each projection of one pair can engage alternately the respective switch cam. The projections are provided with slots 62 to prevent jamming with the switch cam. The wheel 53 rotates once every day and since the actuators rotate at half the speed of the wheel but have two projections the switch cam is partially rotated to effect switching once per day.

Each pair of switching cams 56, 57 actuates respectively noses 70,71 extending from the ends of contacts 72,73 of switches 74,75,76 and 77. Each switch has a third contact 78 engageable by the centre contact. As shown in FIG. 3 the nose 70 is supported by one spur of cam 56 while the nose 71 is free. When the projection 59 engages another spur on the cam 56 the nose 70 drops thus breaking the contact between contacts 72 and 73. Since the cam 57 rotates a spur on cam 57 comes into a position to support the nose 71 so that contacts 73 and 78 make. On continued rotation of the shaft 52 the projection 61 engages a spur of cam 57. Thus causes the spur supporting nose 71 to pull away thus breaking contact between contacts 73 and 78 and a spur on cam 56 to support nose 70 so that contacts 72 and 73 make. The spurs are pointed as shown in order to achieve a rapid break to minimise arcing.

Instead of providing contrate gears, the wheels and pinions of the differential system may be bevelled.

The setting gear wheels may be provided with detents or other friction means (not shown) for securing the wheels in their set positions.

The input drive to the mechanism may be made through the shaft 52 at one end thereof or preferably through a spur gear formed as an integral moulding with the double contrate gear 53 as shown in FIG. 3. lt will be noted from the drawing that the setting wheels are provided on both sides with contrate gears formed as an integral moulding with the disc and finger serrations in order to avoid the necessity of producing left and right hand setting wheels.

What we claim is:

1. A setting arrangement for a time switch comprising:

a driving shaft,

a differential mechanism including a driven gear wheel driven by said shaft,

a setting gear wheel coaxial with said driven gear wheel,

a pinion in mesh with both the driven and setting gear wheels,

said pinion being rotatable about a pinion axis which is free to move about the axis of the wheels along a circular path in a plane between the driven and setting gear wheels, and

actuator means movable with said pinion axis for operating said time switch.

2. A setting arrangement as claimed in claim 1, wherein the pinion axis extends radially from said actuator means which is mounted for rotation about the axis of the wheels.

3. A setting arrangement for a time switch comprising:

a driving shaft,

a driven gear wheel mounted on said driving shaft for rotation thereby,

a setting gear wheel mounted on said driving shaft and rotatable with respect thereto,

a pinion in mesh with both the driven and setting gear wheels,

said pinion being rotatable on a pinion shaft which is free to move about the axis of the two gear wheels along a circular path in a plane between the two gear wheels,

actuator means movable with said pinion shaft for causing actuation of switch means,

said pinion shaft and actuator means being freely rotatable on said driving shaft.

4. A setting mechanism as claimed in claim 3, wherein a fixed shaft arranged parallel to the driving shaft carries a switch cam operable by said actuator means.

5. A setting mechanism as claimed in claim 4 wherein the actuator is provided with a projection which engages the switch cam once in every two revolutions of the drive gear wheel.

6. A setting mechanism as claimed in claim 4 wherein the actuator is provided with two diametrically opposed projections, each of which engages the switch cam once in every two revolutions.

7. A setting mechanism as claimed in claim 5 wherein a slot is provided in the projection to prevent jamming of the projection with the switch cam.

8. A setting mechanism as claimed in claim 1, wherein said setting gear wheel and said driven gear wheel are contrate gears of the same diameter.

9. A setting mechanism as claimed in claim 1, in which the setting gear wheel is provided with a disc 6 having finger serrations and indicia representing hours trate gear through which the two switch cams are operat its periphery m d A settmg mechamsm as clamed m Glam 1 12. A setting mechanism as claimed in claim 11,

wherein a further setting gear wheel is provided which is in mesh with a further pinion meshing also with a fur- 5 wherein a plurality of units comprising the two setting ther driven gear wh e e1 gear wheels, the double contrate wheel between them A Setting mechanism as claimed in claim 10 and the two pinions are provided, the double contrate wherein said further driven gear wheel is integral with g Wheels being driven y 8 C m o S ftsaid first driven gear wheel so as to form a double con- Disclaimer 8,7 7 7 ,582.-Pete1' Robert Durdz'n, New Malden, England. TIME SWITCHES. Patent dated Dec. 11, 1973. Disclaimer filed Nov. 25, 1974, by the assignee, AM F Incorporated.

Hereby enters this disclaimer to claims 1, 2, 3, 4, 5 and 8 of said patent.

[Ofiicz'at Gazette July 1, 1975.] 

1. A setting arrangement for a time switch comprising: a driving shaft, a differential mechanism including a driven gear wheel driven by said shaft, a setting gEar wheel coaxial with said driven gear wheel, a pinion in mesh with both the driven and setting gear wheels, said pinion being rotatable about a pinion axis which is free to move about the axis of the wheels along a circular path in a plane between the driven and setting gear wheels, and actuator means movable with said pinion axis for operating said time switch.
 2. A setting arrangement as claimed in claim 1, wherein the pinion axis extends radially from said actuator means which is mounted for rotation about the axis of the wheels.
 3. A setting arrangement for a time switch comprising: a driving shaft, a driven gear wheel mounted on said driving shaft for rotation thereby, a setting gear wheel mounted on said driving shaft and rotatable with respect thereto, a pinion in mesh with both the driven and setting gear wheels, said pinion being rotatable on a pinion shaft which is free to move about the axis of the two gear wheels along a circular path in a plane between the two gear wheels, actuator means movable with said pinion shaft for causing actuation of switch means, said pinion shaft and actuator means being freely rotatable on said driving shaft.
 4. A setting mechanism as claimed in claim 3, wherein a fixed shaft arranged parallel to the driving shaft carries a switch cam operable by said actuator means.
 5. A setting mechanism as claimed in claim 4 wherein the actuator is provided with a projection which engages the switch cam once in every two revolutions of the drive gear wheel.
 6. A setting mechanism as claimed in claim 4 wherein the actuator is provided with two diametrically opposed projections, each of which engages the switch cam once in every two revolutions.
 7. A setting mechanism as claimed in claim 5 wherein a slot is provided in the projection to prevent jamming of the projection with the switch cam.
 8. A setting mechanism as claimed in claim 1, wherein said setting gear wheel and said driven gear wheel are contrate gears of the same diameter.
 9. A setting mechanism as claimed in claim 1, in which the setting gear wheel is provided with a disc having finger serrations and indicia representing hours at its periphery.
 10. A setting mechanism as claimed in claim 1 wherein a further setting gear wheel is provided which is in mesh with a further pinion meshing also with a further driven gear wheel.
 11. A setting mechanism as claimed in claim 10 wherein said further driven gear wheel is integral with said first driven gear wheel so as to form a double contrate gear through which the two switch cams are operated.
 12. A setting mechanism as claimed in claim 11, wherein a plurality of units comprising the two setting gear wheels, the double contrate wheel between them and the two pinions are provided, the double contrate gear wheels being driven by a common shaft. 